login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A141671
Triangle T(n, k) = n/k if n mod k = 0, otherwise T(n, k) = 0, with T(n, 0) = n+1, read by rows.
2
1, 2, 1, 3, 2, 1, 4, 3, 0, 1, 5, 4, 2, 0, 1, 6, 5, 0, 0, 0, 1, 7, 6, 3, 2, 0, 0, 1, 8, 7, 0, 0, 0, 0, 0, 1, 9, 8, 4, 0, 2, 0, 0, 0, 1, 10, 9, 0, 3, 0, 0, 0, 0, 0, 1, 11, 10, 5, 0, 0, 2, 0, 0, 0, 0, 1, 12, 11, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 13, 12, 6, 4, 3, 0, 2, 0, 0, 0, 0, 0, 1
OFFSET
0,2
COMMENTS
Apparently this is different from A141672. - N. J. A. Sloane, Sep 13 2008
For n, k >= 1 this triangle is the same as A126988(n, k). - G. C. Greubel, Mar 16 2024
FORMULA
T(n, k) = n/k if n mod k = 0, otherwise T(n, k) = 0, with T(n, 0) = n+1.
EXAMPLE
Triangle begins as:
1;
2, 1;
3, 2, 1;
4, 3, 0, 1;
5, 4, 2, 0, 1;
6, 5, 0, 0, 0, 1;
7, 6, 3, 2, 0, 0, 1;
8, 7, 0, 0, 0, 0, 0, 1;
9, 8, 4, 0, 2, 0, 0, 0, 1;
10, 9, 0, 3, 0, 0, 0, 0, 0, 1;
11, 10, 5, 0, 0, 2, 0, 0, 0, 0, 1;
MATHEMATICA
T[n_, k_]= If[k==0, n+1, If[Mod[n, k]==0, n/k, 0]];
Table[T[n, k], {n, 0, 15}, {k, 0, n}]//Flatten
PROG
(PARI) T(m, n)={if(m, if(n%m, 0, n/m), n+1)};
for(n=0, 10, for(m=0, n, print1(T(m, n)", "))) \\ Charles R Greathouse IV, Oct 11 2009
(Magma)
A141671:= func< n, k | k eq 0 select n+1 else (n mod k) eq 0 select n/k else 0>;
[A141671(n, k): k in [0..n], n in [0..15]]; // G. C. Greubel, Mar 16 2024
(SageMath)
def A141671(n, k):
if k==0: return n+1
elif (n%k==0): return n//k
else: return 0
flatten([[A141671(n, k) for k in range(n+1)] for n in range(13)]) # G. C. Greubel, Mar 16 2024
CROSSREFS
Sequence in context: A334441 A278104 A141672 * A309596 A335442 A226247
KEYWORD
nonn,easy,tabl
AUTHOR
EXTENSIONS
Edited by G. C. Greubel, Mar 16 2024
STATUS
approved